Magneto gauge



Patented May 15, 195.1%

MAGNETO GAUGE J ack E. Surline, Philadelphia, Pa. Application October 11, 1946, Serial No. 702,567

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) Claims.

This invention relates to new and useful improvements in magneto assembly tools, and more particularly to a gage for spacing bearings on the ignition cam shaft.

In the assembly of certain magnetos used to furnish ignition current for aircraft automotive engines, an exact spacing is required of the two ball-bearings supporting the shaft carrying the cam which operates the make-and-break mechanism. The design of said magneto is such that these two bears must be assembled in their housing, and held and spaced apart as to be preloaded, so as to revolve under these conditions within certain torque requirements. This condition is maintained so that there will be no play or shake in the shaft on which these bearings are mounted. Such play, if it existed, would cause a variation in the timing of the spark in the various cylinders of the engine for which the said magneto is used in the ignition system.

The assembly of these bearings in their housing and the supporting of said cam shaft Without play or shake, on the one hand, and without undue preloading such as to cause excessive wear and deterioration under normal operation, on the other hand, is a difficult mechanical procedure which this gage is intended to simplify. The adjustment for the amount of preloading of the ball-bearings on the cam shaft is accomplished by the proper selection, as to length, of a spacer which spaces apart the inner races of the two ball-bearings. The gage measures the necessary length of this spacer to give the required preloading of the said ball-bearings, and allows for the measurement and application of the required shaft torque, under which the said bearings are to operate.

The principal object of this invention is to provide a gaging mechanism which will measure the required length of a bearing spacer which preloads a pair of ball-bearings on a magneto cam shaft so that they will revolve, when assembled on their housing mounting and supporting shaft, with a specified torque.

Another object is to provide an adjustable torque measuring device so that a pair of ballbearings on a magneto cam shaft can be assembled in their housing and so4 spaced apart as to revolve, with their supporting shaft, within a specified torque requirement.

Still another object of this invention is to provide a gaging mechanism which permits the assembly of a pair of ball-bearings in a simple and time saving manner so that as the bearings are mounted under operating conditions, they will operate within a specified torque range and loading.

A further object of this Vinvention is to provide an outside measuring device so that the length of the required bearing spacer can be measured with an ordinary depth micrometer, or any other suitable measuring device, easily and quickly,

Y `best operating conditions.

without any particular mechanical skill being required, and with the ball-bearings mounted in their housing and having the required preloading as specified.

These and other objects of this invention and the various features and details of the construction, operation and use thereof, are hereinafter more fully set forth and described with reference to the accompanying drawing in which like numbers refer to like parts and in which:

Fig. l is a half sectional view of my :invention with bearings and the gaging mechanism in place, and

Fig. 2 is an isometric view of a magneto housing with the gage located in its bearings (not shown) Referring now to Figs. 1 and 2, reference numerals 3 and 5 designate ball-bearings having their outer races bearing against shoulders 9 of bearing retainer I0, xed inra magneto Ahousing Il.

Numeral l designates a spindle havinga twostep flange portion intermediate the ends thereof comprising a journal 22 portion and fiange 2 portion to receive the inner race of ball-bearing 3 in snug engagement thereon and thereagainst, respectively. A knurled nut 4 threadedly engages said spindle and is drawn against the inner race of ball bearing 3 to clamp the inner race tightly against flange 2. A threaded plug i3 is screwed axially into the end of the spindle. This plug is of non-ferrous material to receive light mallet blows to aid in the disengagement of the bearings.

The other end of spindle l is provided with a sleeve 5 having a two-step flange portion at the end thereof comprising a journal 23 and ange 24 which receives the inner race-of ball-bearing 6 in snug engagement thereon and thereagainst, respectively. A sheave 1 threadedly engages said sleeve at I9 and is drawn against the inner race of ball-bearing 5 to clamp the inner race tightly against flange 24. Micrometer nut 8 threadedly engages the end of the spindle and bears against the end of sleeve 5 to adjust the position of said sleeve and its associated inner race toward the fixed inner race of ball-bearing 3, thereby lightly loading the bearings. The amount of pre-loading is adjusted so that the ball bearings just revolve within specified torque limits applied to sheave l thru cord Il secured in slots 20 and guided in groove 2|.

The gage is so designed that when assembled in place between two Subsequently preloaded ballbearings, the .distance l5 being the length of the required spacer (not shown) is identical with the distance I4 measured from the end of the spindle to the outer end of knurled nut 8 and easily measured by a depth micrometer (not shown) through bore I6. The gage measures the length of the spacer necessary to give the required pre-loading on said ball-bearings for the The flange end of .purposes without the payment of any royalties thereon ortherefyor. v -fleimr 1.A gage, cemprising: aY rod-like axisv member havingmeans thereon to receive a iirst vballbeerinecfzaxially therewith .and in fixed engagementthereonya member movable axially on said axis, member` and- 4 having meansto receive a second ball-bearing coaxially therewith and in fixed engagement. thereon andspaced from said rst ball-bearing; andan velongated micrometer nut engaged with said axismember'to bear against the other4 member, said elongated micrometerv nut being so constructed and arranged'that it always extends beyondvthe end of` said axis member an amount proportional tothe .distance between the ends lof the vyii'rst-mentioned and second-mentioned means adjacent their respective ballbearings.

2.- A gage, comprising; a. rod-like axis elemen' having 'rriearis"thereonY to ixedly receive thereagainst ..a-rst, ball-bearing coaxially therewith intermediate theendsfthereof; a sleeve slidably engaged onore eridlof said element and having meanstolxedly'receive thereagainst a second ballbearing coaxiallytherewth and spaced from saidrst ballbearing ;Av andan elongated micrometer nut threadedlyfengaged with said one end ofsaidelement tobear against said'sleeve, said elongated micrometer nutbeing so constructed and arrangedrthat'it always lex'ten'dsfbeyond said one end of said 'elementfanfamount proportional tvthe distancebetween the ends of the firstnentioned land Vseco'nd-rnentione'd means against which are received their` respective ball-bearings.

3. The gage describedinclaim 2 and a compression. szirngl betweenfsaid element and said Asleeveto spring load saidslee've.

,4. A gage,Y comprising: an axis element having la .twe-step lportion intermediate the ends thereof comprising "a journal and aflange adapted to. receive a v'iirst ball-bearing thereon and thereagainst, respectively; kamnut o threadedly engaged with. said velement tofforcethe inner race of said ball-bearingagainst fsaid flange; a sleeve slidably engaged on the end of. said element opposite saidnutsaid sleeveliaving a two-step end portion comprisingr a journal and aange adapted toA receive. a second ball-bearing thereon and thereagainst, Y respectively; a compression spring betweensaid element and said sleeve tofspring load said sleeve; an elongated micrometer nut threadedly engaged with ,said end, of;v said .element and bearingagai'nst said spring loaded sleeve, said .elongated Vmicrometer nut beingfso/'constructe'dvand arranged that it always extend'sbeyondthe end of, said elementari amount (equal to f the distance .between the shoulders of said anges; :and ahsheave threadedlycengaged with said sleeveito `force the inner .race ofUsaid/second .ballbearing` against thekiiange :of saidsleeve, and y, ada'ptedto receive a predeterminedY torque.

54 ,e gegeorerrisieg.;@gaat margherite means thereon ff edlyfpesitioeng chreagainsttheinnerirace oi'ag first bearingan axially shiftable member carried by said axisy member and having means for xedly positioning there- 5,

#from said first bearing, and means axially adagainst the inner race of a second bearing spaced Ajustably` mounted on said axis member for bearing against said` shiftable member, the position of said last-named means with respect to said axishmember indicating the distance between the ends of the second-mentioned means against which are positioned their respective races.

,6. A gage. accordingitdclaim, 5 andresilient meansbetween saidmembers to` load said shift- @elementen 7. A gage comprising an axis -rrtlember, having means thereon ,for l:positioning thereagainst. a raerpf a ernst bearing; a siidabie member 1intein axis member .having means for positioning'thereagainst a raceofvfya, second bearingv spacedY from said rstbeari'rg,"andmmeans axially adjustably mounted on said,axismemberv :for bearing against Ysaid 'slidablefmemben the position of; said lastn'amed'inean's` 'with respect. to said axisv member indicating thee-distance betweenthegends of the first and` secondi-mentioned means againstywloich are positioned theirirespective races.

8. A gage according,to"claim,'7,. and resilient means between said members toiload said slidable member. Y

'19. ,A gage, comprisingfan xaxis member yhaviruig a two-step vpor-tion intermediate, theends thereof comprising a journal, andi* al Hnge for ,T @CQYng ai-lrst .ball.-Joea1iing thereonand thereagainst, Arespeetivel'y; a'sleeve slidably-,engaged on onel en d of .said member .and havingf aftwo-step end portion comprisingafjournalland a,flange forr receivingeJ second' ballfbearing. thereon and thereagainst, respectively; andymeans threadedly `engagedwith saidaxis memberat said one end and bearingagainst ,said sleeve, said Ymeans being constructed to extend :beyond said one end of said member an amount, equal to the distance between. theshoulde s of,` 4said flanges.

V.$10. VAgage comp isimnganaxis member having aAiiange,,intermekzliatej theends thereof for receiving'a, iirst ball-,bearing thefreagainst; a sleeve Slidablv mounted ,n ,one-end of said` member and having a flange at one end thereof for receiving thereagainst ua.l second .ball-bearing; and means axiallyadiustably ,mounted at said one end of saidrnelnber and. bearing against` said sleeve, saidmeans :being constructed to extend beyond. said one eridvofrsaid member Aa 'distance equal to theldistance'between the shoulders of said flanges. v

JACKl sURmNE.

.aanifiltnivclesA CITED Theifollowing referencesarenf record in the iile of this patent:

YPATENTS 

